China is marking 50 years since a failed Tibetan uprising against Beijing's rule this week with a wide-reaching security clampdown in the Himalayan region, one year after the anniversary sparked violent rioting across western China.

The crackdown has drawn international attention to the Tibet issue, and sparked the ire of the Dalai Lama. The move comes as China's foreign minister arrives in the United States. Originally meant to shore up goodwill between the two countries, the trip must now address a US-China naval dispute in the South China Sea and outcry over Tibet, reports the Associated Press.

Located on a high Himalayan plateau, Tibet makes up about one-quarter of China's landmass and was conquered in 1951. Since then, it has been divided between the Tibet Autonomous Region and China's Qinghai Province. (Click here to see a map of the region.)

The Times (of London) reports that regular police, riot police, and units of the state-backed paramilitary People's Armed Police have flooded Tibet's capital city, Lhasa. Brandishing firearms, they have taken up positions on street corners, rooftops, and around the perimeter of the Jokhang Temple, one of the holiest sites in Tibetan Buddhism.

Chinese authorities have also disrupted cellphone service, in the hopes of impeding the organization of any demonstrations.

Few pilgrims were to be seen yesterday. Stalls selling marigolds and hunks of yak butter were closed. One Lhasa resident, who declined to be named, said: "The atmosphere is pretty tense. There are more armed police than normal but it isn't as much as when the Olympic torch was here. Then every road was closed off."

One hotel employee said: "There are armed police around the temple. You need to keep your ID with you because the police are checking."

Mobile phones in the city were virtually useless because of signal interference, residents said. China Mobile had notified subscribers that the system would undergo maintenance from March 10 until April 1 — a move seen as intended to prevent Tibetans from sending text messages, thereby spreading word of any unrest.

According to Human Rights Watch, detainees are to be held in these facilities until they can be deported to neighboring provinces. Some are told they will be held until after March "for security reasons."

Satellite pictures examined by Human Rights Watch matched the description given by one eyewitness of large, walled facilities with several watchtowers overlooking rows of multi-storey buildings organized around a yard. No other independent confirmation could be immediately obtained given the current restrictions on movement in Tibet.

Speaking to reporters in Dharamsala, India, where he has led the Tibetan government-in-exile since 1959, the Dalai Lama said that living under Chinese rule for 50 years had "brought untold suffering and destruction to the people of Tibet," reports the Financial Times.

The Dalai Lama is a staunch proponent of peaceful compromise with China, and points out that Tibetan autonomy is both outlined in the Chinese Constitution and was promised to the province by Mao Zedong in 1954 and 1955. His strong language this week was seen by many as a reaction to the Chinese crackdown.

Chinese policies in Tibet "thrust Tibetans into such depths of suffering and hardship that they literally experienced hell on earth", the exiled Tibetan leader said in the Indian hill town of Dharamsala....

The Dalai Lama said Chinese policies had led to "the deaths of hundreds of thousands of Tibetans". He said he still supported the "middle way" approach of calling for greater autonomy for Tibet within China, rather than independence. However, the strong language employed by the 73-year-old monk, who has had several health scares in recent months, raised concerns that he might never reach a political deal with China.

"Even today, Tibetans within Tibet live in constant fear and the Chinese authorities remain constantly suspicious of them," he said.

Last year's commemoration of the 1959 uprising led to weeks of violent rioting in several parts of western China, after Chinese security forces began suppressing protests in the Tibetan capital. They were the most serious challenge to the Chinese government in decades.

The New York Times reports that, according to Chinese officials, rioting in Lhasa killed 19 people, mostly ethnic Han Chinese shopkeepers and civilians. In the "violent repression that followed," the Times says 220 Tibetans died, almost 1,300 were wounded, and nearly 7,000 were detained. One year later, over 1,000 Tibetan civilians are still said to be missing.

Chinese government officials told the Times that only 953 people were detained after the riots. They said 76 were charged with crimes like arson and robbery, while the rest were released.

The government daily repeated Beijing's version of events, which paints the Dalai Lama as the overlord of a vast serf- and slave-holding society in the Himalayas. To commemorate what the government views as its liberation of Tibet, it has declared March 28 to be Serf Emancipation Day.

March 10 marked the 50th anniversary of the foiling of an armed rebellion staged by the ruling class in Tibet to preserve serfdom and theocracy. The central government implemented democratic reforms and abolished serfdom in Tibet after the Dalai Lama fled to India in 1959.

"If freedom-loving people do not speak out for human rights in China and Tibet, then we lose the moral authority to talk about it in any other place in the world," she said to loud applause.

The United States has pledged not to let human rights differences get in the way of working with China on other issues, such as trade. But the crackdown in Tibet, and the attention it has attracted from human rights groups as well as Congress, does not make that easy.

"The United States respects the territorial integrity of the People's Republic of China and considers Tibet to be part of China," Wood's statement said. "At the same time, we are deeply concerned by the human rights situation in Tibetan areas."